The present invention relates to the field of gas turbine engines and more particularly to that of bypass turbojet engines.
It relates more specifically to a device for actuating a shutter in a turbojet engine, to a bypass air bleed system equipped with such an actuating device, and to a turbojet engine comprising these.
An aircraft bypass turbojet engine comprises, as is known, a primary gas flow duct and a secondary gas flow duct, which ducts are separated by an inter-duct compartment of an intermediate casing. Positioned in the primary duct, from the upstream direction downstream with respect to the direction in which the gases flow, are a low-pressure compressor and a high-pressure compressor. The air thus compressed is conveyed to a combustion chamber in which it is mixed with pressurized fuel which is burnt to provide, downstream of the combustion chamber, energy to a high-pressure turbine which drives the high-pressure compressor and then to a low-pressure turbine which drives the fan and the low-pressure compressor. The gases leaving the turbines provide residual thrust which is added to the thrust generated by the gases flowing through the secondary duct in order to provide the motive power for the aircraft.
Under certain flight conditions the amount of air delivered by the low-pressure compressor is too high to guarantee correct operation of the turbojet engine, and so it is necessary to divert some of this air from the primary duct to the secondary duct so as to avoid the onset of the phenomenon known as surge which is caused by the separation of the streams of fluid along the vanes and which causes instability in the flow. These openings can also be used to remove foreign bodies such as ice or water ingested by the engine.
This diverting of air is also known as air bleeding. It is performed using bypass air bleed systems which employ articulated moving shutters actuated simultaneously by a set of actuating means.